It has long been known in the art that fractures in long bones, such as the femur, can be successfully treated through the use of bone plates or intramedullary nails that have lengths many times longer than their widths. The nail or plate is positioned to span the fracture, and attached on opposite ends directly to the bone. While the fracture is healing, the plate or nail prevents twisting and lateral movement in the fracture area, and carries loads across the fracture that the bone is otherwise unable to support. After the fracture has sufficiently healed, the bone plate or intramedullary nail may be detached from the bone and removed from the patient.
In most instances, bone plates and intramedullary nails are made from a suitable surgical grade metallic alloy and are machined with openings that are sized to receive attachment screws at an implantation site. In most instances, these openings do not include threads and have a diameter just larger than the fastening screw. With this arrangement, the fastening screw acts as a pin with respect to the bone plate or intramedullary nail and prevents the same from either rotating or moving laterally with respect to the fractured bone. As a consequence, physicians generally do not have wide latitude in choosing a location through which to drill a fastening bore through a bone. Generally, the fastening bore is drilled perpendicular to the long axis of the bone and through the corresponding opening in the bone plate or intramedullary nail. In general, an improved treatment of the fractured bone can be obtained if the physician has some freedom in choosing the best location on the healthy portion of the bone for attachment of the nail or plate to the bone. In order to gain any freedom in choosing an attachment point with present systems, a physician must often times move the plate or nail to a position that provides less than an optimal support and positioning across the fracture site.
The present invention is directed to overcoming these and other problems associated with the treatment of fractures in long bones.